Scallions are a larger species of bunching onions, while chives are a smaller type of onion. They are very similar and are often used in soups, baked potatoes and egg dishes.
Chives and scallions belong to the same family. Chives grow well, though slowly, in sunny environments with moist soil. Scallions are also known as green onions or spring onions, and they can have a mild, sweet or sharp flavor. Scallions do not have a bulb, although other varieties of green onions do. People can harvest them when their leaves are 8 to 10 inches tall. Chives do have a bulb, and people should harvest them when they reach 6 inches tall.